NextEra Energy Resources LLC expects to permanently cease commercial operations at its 622.1-MW Duane Arnold Energy Center in Iowa in late 2020.
In connection with this, the NextEra Energy Inc. subsidiary and Alliant Energy Corp. agreed to shorten an Alliant utility's purchase agreement for the output of the nuclear plant by five years in exchange for a $110 million buyout payment to NextEra.
Duane Arnold started operating in 1975, and its PPA with Alliant subsidiary Interstate Power & Light Co. ends in December 2025, according to S&P Global Market Intelligence data. The single-unit plant in Linn County, Iowa, is licensed to operate to 2034. NextEra acquired Alliant's interest in the plant in 2006. Central Iowa Power Cooperative owns a 20% share of the plant and Corn Belt Power Cooperative owns the remaining 10%.
NextEra Energy executives said in January they would will likely close the power plant if the PPA were not renewed and they could not find a replacement customer.
Alliant Energy plans to seek approval from the Iowa Utilities Board to recover its buyout payment, according to a July 27 news release. If approved, Alliant expects savings of nearly $300 million, on a net present value basis, for its Iowa customers starting on or before Jan. 1, 2021.
To partially replace energy from Duane Arnold, NextEra Energy Resources will supply wind energy from four repowered Iowa wind facilities, totaling approximately 340 MW, under new power purchase agreements with Alliant Energy.
Central Iowa Power supplies power to 13 member cooperatives, and said its share of the Duane Arnold plant makes up more than one-third of its power supply portfolio. Since NextEra's announcement in January, the co-op has been investigating other resources and working on a new integrated resource plan. "This presents an opportunity to explore additional resources with reliability remaining a long-term priority," co-op CEO Bill Cherrier said in a statement.
NextEra Energy Resources also plans to invest approximately $650 million in existing and new renewables in Iowa by the end of 2020, including the $250 million repowering of the four wind facilities.
NextEra Energy Resources plans to notify the Midcontinent ISO and the U.S. Nuclear Regulatory Commission of its intention to permanently cease operations and decommission the power plant. The company is evaluating redevelopment opportunities at the Duane Arnold site, including the construction of new solar energy, battery storage or natural gas facilities.